This invention includes protective devices for protecting against needle-stick injury by a medical catheter or needle. More particularly, the invention is concerned with guards for use with wingless needle assemblies of the type used by blood banks. However, it is also applicable to winged needle assemblies used for other medical purposes, such as the intravenous (IV) infusion of fluids. The needle or catheter assemblies of the type concerned here, comprise a needle, a needle mount or block, and a flexible tube, which are connected at one end to the needle via the needle mount and at the other end to a blood collection bag or to an IV fluid source. A winged catheter or needle assembly is one having a pair of flexible wing-like protrusions extending laterally from its mount, the wings being taped to the user's skin to keep the needle in place over the long periods of time often needed for IV infusions.
To use a wingless needle assembly for blood collection, the phlebotomist holds the needle mount with the bevel of the needle facing upwards and inserts the needle into a vein in the donor's lower arm, which is supported substantially horizontally. The tube of the assembly may then be taped to the donor's arm to hold the needle in place for the few minutes during which a unit of blood (generally 500 ml) is withdrawn. To remove the needle, the phlebotomist removes the tape, grasps the mount and withdraws the needle while pressing a swab onto the puncture site. The tube is then stripped of blood, sealed and cut so that the needle can be disposed of in a `sharps bin`. It is during the latter actions that there is significant danger of needle-stick injury and/or contact with blood exuded from the needle (`blood-splash,` contact).
Another difficulty with this procedure is that, since the needle mount has no wings, it is readily rotated and moved by the resilience of the previously coiled tube. Even taping the tube in place often does not prevent further rotation of the needle mount. Such rotation is undesirable, as it is likely to place the bevel of the needle against the side or bottom surface of the donor's vein, thereby occluding the lumen and restricting blood flow. Rotation or longitudinal movement may also result in the point of the needle scratching or piercing the internal wall of the vein.
U.S. Pat. No. 5,376,075 to Haughton discloses a tubular needle guard that permanently houses the needle and its mount, the needle being extended from the device to allow venipuncture and then being snapped back into the device under spring action after use. The guard is provided with flexible wings by which it and the extended needle can be manipulated to effect the venipuncture. International patent application WO 92/04073 by Van den Haak also discloses a tubular needle guard that is provided with wings whereby the needle may be inserted and stabilized after insertion. Such devices require specialized needle assemblies and cannot be used with standard bloodpack needle assemblies, which have needle mounts that vary in shape according to manufacturer or model. Moreover, these prior art guards deny the phlebotomist the direct control and feel obtained when the needle mount itself is gripped to effect needle insertion in the normal way.
U.S. Pat. No. 5,112,313 to Sallee discloses a needle guard suitable for use with a wide variety of wingless needle assemblies. This guard is simply an open box that is inverted over the needle and mount after needle insertion and is secured to the patient or donor's skin by means of integral self-adhesive flaps. The guard is intended to prevent the needle mount from being inadvertently knocked after needle-insertion. It does not fit closely enough over the needle mount to restrain it against movement or rotation via the tube and does not prevent needle-stick or blood-splash after the needle is withdrawn.